The ammunition in test (10 rounds) would need to fit this established profile.

Nothing in the sample over 40500 psi

Here is something to consider...The pizoelectric transducer system employs the transducer flush mounted inside the chamber of the test barrel. Pressures developed by the expanding gases to the cartridge walls causing the transducer to deflect creating a measuerable electrical charge. This change is then converted to a pressure reading in psi.

Systems being sold are being used on the outside of the chamber of the test barrel. The expanding cartridge is not directly acting upon the transducer as in the SAAMI testing.

Proof Pressures for 10mm are 130% minimum and 140% maximum as set by SAAMIThe formula is based on the Maximum Portable Lot Mean MPLM of 38,700 psi 38,700 x 1.30 = 50,310 psi and 38,700 x 1.40 = 54,180 psiMinimum and Maximum50,310 psi - 54,180 psi these would be rounded to 50,500 psi - 54,000 psi

« Last Edit: January 14, 2014, 08:23:32 PM by The_Shadow »

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The "10mm" I'm Packin', Has The Bullets Wackin', Smakin' & The Slide is Rackin' & Jackin'!NRA Life MemberSoutheast, LoUiSiAna

Thanks, please look up at the 2nd post I added the SAAMI pressure map of 10mm as stated in Pub. # 205.Does anyone have the Quick Loads Software?If yes...then maybe we could run some models like this one for given data powder specific. We could actually post that in the "Reloading Section"

Just as a reference for the 9.4 grain LongShot load that I tested here is a screen shot of the Quick Load program which a friend has run for me so I will share it here...

As you can see the pressure is shown above that of the SAAMI MAP for 10mm. I don't know exactly how accurate the data is, but the 58,823 psi was the predicted peak.

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The "10mm" I'm Packin', Has The Bullets Wackin', Smakin' & The Slide is Rackin' & Jackin'!NRA Life MemberSoutheast, LoUiSiAna

Just as a reference for the 9.4 grain LongShot load that I tested here is a screen shot of the Quick Load program which a friend has run for me so I will share it here...

As you can see the pressure is shown above that of the SAAMI MAP for 10mm. I don't know exactly how accurate the data is, but the 58,823 psi was the predicted peak.

Interesting. 200gr XTP...9.4gr Longshot...I'm probably blind but don't see what primer was used...equaling peak psi of 58,823. Not sure what to think, just that it seems like too high of a peak for that load even at a COL of 1.250". I really don't know, but just don't see that load hitting any more than 50,000 psi, and more than likely less. Do you know what primer was used? If it wasn't anything more than a standard large pistol, and the case wasn't roll crimped into the bullet, I'm just not seeing it.

I am not familure with the software, nor do I have the QuickLoads program. A person from one of the forums plugged in the data for the load, then e-mailed this copy of the screen shot. I don't know if the program allows for different primer imput. As to the accuracy, I have no way of knowing...however this data was based off loads that I have personally loaded, tested and were the same as sold by SwampFox ammo.

In my test of the 200gr XTP over 9.4 grains of LS, I used the CCI350 and saw 1260 fps from the 5" S&W

If this data is truely showing 58,823 psi and is anywhere close to that level in the real loads, then the 10.0 grain loads used in the 200gr XTP @ 1325 fps would actually be higher...

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The "10mm" I'm Packin', Has The Bullets Wackin', Smakin' & The Slide is Rackin' & Jackin'!NRA Life MemberSoutheast, LoUiSiAna

I am not familure with the software, nor do I have the QuickLoads program. A person from one of the forums plugged in the data for the load, then e-mailed this copy of the screen shot. I don't know if the program allows for different primer imput. As to the accuracy, I have no way of knowing...however this data was based off loads that I have personally loaded, tested and were the same as sold by SwampFox ammo.

In my test of the 200gr XTP over 9.4 grains of LS, I used the CCI350 and saw 1260 fps from the 5" S&W

If this data is truely showing 58,823 psi and is anywhere close to that level in the real loads, then the 10.0 grain loads used in the 200gr XTP @ 1325 fps would actually be higher...

Talking out loud.....SAAMI Maximum Average Proof Pressure (ONLY EVER for the development of new gun platforms by new gun manufacturers, and NEVER for general ammo to be loaded to) is listed as 54,000psi......SAAMI Maximum Probable Lot Mean (the PSI of which NO load meant to be at Maximum Average Pressure should ever exceed) is listed as 38,700psi......Glock 10mm barrels have very poor 6 o'clock chamber support.......you have accomplished 9.4gr of Longshot, in conjunction with a magnum primer no less, without catastrophic failure in a S&W platform.......old man Willard (may he RIP) according to his claims sold 200gr XTP loads with 10.0gr of Longshot to the open-market with the stipulation of aftermarket barrels better supported in the 6 o'clock position needing to be used and 22 lb spring (per the link you put up in "180gr bullets over Longshot")........and QuickLoad says 58,823psi for 9.4gr loads with a 200gr XTP.........I don't know, but DEFINATELY a stretch for my mind to go with QuickLoad's calculations. Big stretch! Who knows.

Mike of SwampFox used an 8" pressure testing barrel and had mentioned the pressures of those loads to be inside the SAAMI spec. As for the 10.0 grain load I read where he mentioned that pressure to be 1000-1500 psi higher than the 37,500 psi but the still sort of fit the MAP. (his words and testing) Personally, I stopped at 9.4 grains of LongShot with the 200 XTP's based on my testing with my guns.

He had made notes of the use of aftermarket barrels, barrels longer that 4.6" and using 22lb springs for best results...

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The "10mm" I'm Packin', Has The Bullets Wackin', Smakin' & The Slide is Rackin' & Jackin'!NRA Life MemberSoutheast, LoUiSiAna

And, as I recall, internal ballistics is one of those areas where lots of empirical testing still occurs because there are more variables than can be easily accounted for. Even what are nominally small changes in the chamber can have a big impact on results.

I have read that quickloads case capacity values are always minimum to account for thicker brass and it's impact. This could certainly account for the difference between these readings and what Mike had with his pressure barrel.